J-PARC RCS次世代LLRF制御システムの導入

抄録

The Low Level RF (LLRF) control system for the Rapid Cycling Synchrotron (RCS) of the Japan Proton Accelerator Research Complex (J-PARC) plays an important role in acceleration of high intensity beams. The key functions of the original LLRF control system are the dual harmonic auto voltage control and the multiharmonic RF feedforward for compensation of the beam loading in the wideband cavity. The original system had been working well without significant problems for more than a decade, however, the long term maintenance became difficult due to the obsolesce of the old FPGAs in the system. Therefore we developed and deployed the next-generation LLRF control system. The next-generation system is based on the modern platform, MTCA.4. The most important new function of the system is the multiharmonic vector RF voltage control feedback, which compensate the heavy beam loading in the wideband cavity better than the feedforward at the beam intensity of the design beam power, 1 MW. The commissioning results are reported. The next-generation system has been successfully deployed.